Teaching fast player to play fast against slow opponents

I see this alot where better players will play down to lesser talent, be it in practice sessions or games.
My 04 boy is like this. He has performed well above his club placement at certain tryouts and camps but unfortunately also good at playing down against lower competition. Seeing this right now in h.s. setting...

How do you snap a player out of this? I thought videos would help but in my opinion everyone already looks slow on video...

Ideas?